The objective of this project is to elucidate the inter-relationship between molecular composition of the plasma membrane and the functions that the membrane building blocks serve in transport, bioelectrogenesis and inter-cellular communication. Plasma membranes are isolated from tissues (brain) or from cultures of CNS derived cells and membrane-characteristic macromolecules are studied, isolated and purified. In particular the function of membrane ecto-enzymes was one of the objectives of our studies. Some of this work may have a possible bearing on the biochemistry of CNS cells in convulsive diseases. We have found that in seizure-prone mice (DBA) there is a deficiency of a Calcium-activated ATPase. This ATPase is probably identical with one of the ecto-enzymes, which we identified in glia or neuroblastoma. Other animal models of epilepsy are studied.